Guillotine blade geometry

[KrisNZ]

Hello, does anyone here have any experience with edge geometry of guillotine blades used in the printing industry?

 

[HeavyHanded]

Hello, does anyone here have any experience with edge geometry of guillotine blades used in the printing industry?

I'll get back to you on that. Can I ask why?

 

[KrisNZ]

I'll get back to you on that. Can I ask why?

Sure, we primarily produce paperbacks, the problems is the digital toner used on our print engines. It cracks when we do the final trim, the standard angle of our blades is 24 deg. Im thinking if i reduce that angle by 2-4 deg. might help with this

 

[HeavyHanded]

Sure, we primarily produce paperbacks, the problems is the digital toner used on our print engines. It cracks when we do the final trim, the standard angle of our blades is 24 deg. Im thinking if i reduce that angle by 2-4 deg. might help with this

Does it happen with a fresh blade?

 

[HeavyHanded]

Pretty sure our blades are set at 28° at the edge, or used to be anyway. We do a lot of cutting of dry toner print and normally only have trouble with folding across the grain.

I wouldn't want to go more acute than 24° as longevity is definitely going to decrease.

Is there drift or any other indication of weak clamping pressure?

Ultimately, you might have to go with some sort of aqueous or other surface coat.

 

[KrisNZ]

Yip, it cracks with a fresh blade, clamp pressure is good, aqueous coatings a no go for us.



Ive an old blade that im going to get reprofiled by 2 deg. and see how that works. It my reduce life but if it reduces the problem it may be worth it.

Ill let you know how I get on.

Thanks for the input.

Kris,.

 

[HeavyHanded]

Please let me know how that goes.

I'd still consider more clamping pressure, especially if you can get it to cut flat samples of the same material.

If it cracks anyway then going more acute is probably the best call.

 

[KrisNZ]

Please let me know how that goes.

I'd still consider more clamping pressure, especially if you can get it to cut flat samples of the same material.

If it cracks anyway then going more acute is probably the best call.

Clamp pressure is a double edged sword, to much and you crush the spine not enough and you get associated problen with that as well.

Ive sent the blade off to get reprofiled. Ill let you know how i get on.

Kris

 

[HeavyHanded]

Clamp pressure is a double edged sword, to much and you crush the spine not enough and you get associated problen with that as well.

Ive sent the blade off to get reprofiled. Ill let you know how i get on.

Kris

Cool, I'm interested in the solution. Short run stuff you run into all sorts of problem solving during finishing.